Cushion for a Vehicle Seat

ABSTRACT

A cushion for a vehicle seat has a cushion layer arrangement that is covered by a cushion cover. The cushion layer arrangement includes an air-conducting cushion layer into which air can enter via at least one air inlet and from which the air, after flowing through it, can exit via at least one air outlet which is assigned at least one air outlet opening. At least one air outlet opening is arranged within the cushion cover.

This application is a national stage of International Application No. PCT/EP2007/000328, filed Jan. 16, 2007, which claims priority under 35 U.S.C. §119 to German Patent Application No. 10 2006 003 880.0, filed Jan. 27, 2006, the entire disclosure of which is herein expressly incorporated by reference.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a cushion for a vehicle.

In a cushion of this type, such as disclosed, for example, in German patent document DE 199 20 062 C2, a cushion layer arrangement comprises a foam layer resting on a cushion support, an air-conducting cushion layer arranged thereabove and a moisture-permeable top layer in the form of an open-pore foam arranged thereabove in turn. In order to ventilate the seat, a fan is arranged within the lower foam layer; the air flow of the fan passes via an air inlet into the air-conducting cushion layer. Over the course of its passage through the air-conducting cushion layer, the air flow, which is relatively cool and dry, absorbs body moisture from the seat occupant. Such moisture can pass via a cushion cover covering the cushion layer arrangement and the top layer arranged therebelow (composed of open-pore foam), into the region of the air-conducting cushion layer. After flowing through the air-conducting cushion layer, the air flow transporting the body moisture exits via an air outlet at the front and rear end of the air-conducting cushion layer or of the cushion itself. For this purpose, openings are provided between the cushion cover and the lower foam layer.

Accordingly, in this arrangement, the air flow generated by the fan must cover a relatively large distance within the air-conducting cushion layer, before it can exit either at the front or rear end of the cushion. Thus, at least one fan which ensures and/or assists circulation of the air flow flowing through the air-conducting cushion layer, must be provided in the region of the lower foam layer.

It is therefore an object of the present invention to provide a cushion for a vehicle seat of the type mentioned above, in which an improved air flow can be created within the air-conducting cushion layer.

This and other objects and advantages are achieved by the cushion according to the invention, in which at least one air outlet opening is arranged directly within the cushion cover. In other words, at least one air outlet opening is therefore positioned in the direct vicinity of the vehicle occupant's body, so that air flowing through can leave the air-conducting cushion layer at a significantly earlier point. Preferred positions for the arrangement of the at least one air outlet opening within the cushion cover are, for example, a front central region of a seat area of a seat cushion, an upper central region of a seat area of a backrest cushion or a corner region of the side cheek of the cushion, between an upper surface and a lateral side of the cushion. Experience has shown that these positions are not covered by the seat occupant, and therefore a constant circulation of air is possible.

In the region of the seat occupant, the air flow into the air-conducting cushion layer can absorb the body moisture, which passes via the cushion cover in the direction of the air-conducting cushion layer, and can transport it away over a relatively short distance via the at least one air outlet opening arranged within the cushion cover. Overall, a highly intensive circulation of air within the air-conducting cushion layer can therefore be provided with air saturated to an appropriate extent with body moisture flowing out via the air outlet opening within the cushion cover and fresh air then flowing in via the air inlet.

Furthermore, it has been shown to be particularly advantageous to arrange the at least one air outlet opening in a front central region of the seat area of a seat cushion. This region which is normally located between the thighs or knees of the seat occupant, has the advantage of being covered by the seat occupant, only very rarely. Therefore, circulation of the air within the air-conducting cushion layer can be particularly reliably ensured.

In a further refinement of the invention, it is also shown to be advantageous to arrange both a seat cushion and a backrest cushion in the region of the side cheeks. Experience has shown that in this region there is also no risk of the air outlet openings being covered by the seat occupant, particularly in a corner region between a front top side and an end side of the cushion.

If a backrest cushion is to be provided, it has been shown to be advantageous to arrange the at least one air outlet opening in an upper central region of a seat area of the backrest cushion. This region, above the occupant's shoulders, is also usually not covered by the seat occupant, and therefore circulation of the air within the air-conducting cushion layer can also be reliably ensured there.

If a plurality of perforation openings is provided within the cushion cover, then, all in all, an air outlet opening arrangement which can be inserted unobtrusively into the overall image of the seat cover can be provided.

In a further refinement of the invention, a top cover which is arranged between the air-conducting cushion layer and the cushion cover has been shown to be advantageous. Such top cover is of open-pore and moisture-permeable configuration, and therefore body moisture from the seat occupant can pass via the cushion cover and the top layer in the direction of the air-conducting cushion layer, where it is absorbed by the relatively dry and cold air flow circulating within the air-conducting cushion layer and is conveyed outside the cushion. Within the top layer it is possible, for example, for the lines of a resistance seat heater to be integrated in a simple manner. Furthermore, the air-conducting cushion layer, which is made, for example, from a “spacer knit” or from rubberized hair and is accordingly stiff, can be cushioned by the top layer. So that the air mixed with the body moisture can pass out of the air-conducting cushion layer, the top layer is made at least in some regions from a highly air- and moisture-permeable material or else it has corresponding passage openings.

In a further refinement of the invention, it has been shown to be advantageous to arrange the air inlet below the air outlet. In this manner, a chimney effect can be obtained such that fresh air flowing in (for example, on the lower side of the cushion), after flowing through the air-conducting cushion layer, flows in the direction of the air outlet arranged thereabove, solely on account of being heated by the body moisture. If—as provided according to the invention—the flow paths within the air-conducting cushion layer are shortened, then the chimney effect can be realized particularly readily. As a result, it is therefore possible to ventilate the seat without the use of additional fans. However, even if additional fans are used, a readily circulating air flow is always ensured.

Finally, it has been shown to be advantageous to arrange the air inlet offset in relation to the air outlet, which results in a flow of air through the air-conducting cushion layer in order to absorb body moisture from the seat occupant, with direct passage of the fresh air from the air inlet to the air outlet being impossible.

Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a and 1 b respectively show schematic top and side views of a seat cushion of a vehicle seat, with a plurality of air outlet openings provided in a central front region of a seat area (FIG. 1 a) and in a corner region between a front top side and a lateral end side (FIG. 1 b) of the seat cushion, via which air outlet openings an air flow can escape from the seat cushion;

FIG. 2 shows a schematic sectional view along the line II-II in FIG. 1, with an air-conducting cushion layer being provided, into which air can enter via a plurality of air inlet openings, and from which it can exit via a plurality of air outlet openings; and

FIG. 3 shows a schematic front view of a backrest cushion in which an upper central region of a seat area has a plurality of air outlet openings.

DETAILED DESCRIPTION OF THE DRAWINGS

FIGS. 1 a and 1 b illustrate, in respective schematic top and side views, a seat cushion which essentially comprises a centrally arranged seat area 10 and two side cheeks 12 running at the sides thereof. In this case, the seat area 10 and the side cheeks 12 are separated from each other via basted seams 14. A further basted seam 16 divides off a rear seat area 18 from the seat area 10. A plurality of air outlet openings 20 of an air-conducting cushion layer 32 (explained in further detail below in conjunction with FIG. 2) are provided in a front center region of the seat area 10.

As shown in FIG. 1 b, further air outlet openings 20—preferably designed as perforation openings—can be provided in a corner region 26 between an upper or top surface 22 and an outer side 24 of the side cheek 12. In the present exemplary embodiment, the air outlet openings 20 therefore are distributed over virtually the entire length of the corner region 26.

FIG. 2 shows the construction of the cushion in a schematic sectional view along the line II-II in FIG. 1 a. The top side of a seat cushion support 28 (which is supported on a seat underframe, not shown) supports a lower cushion layer 30 which can be composed, for example, of an air-impermeable foam, an air-permeable rubberized hair composite, or the like. The seat cushion support 28 is preferably composed of plastic or metal. The air-conducting cushion layer 32 which, in the present exemplary embodiment, is designed as a spacer knit is provided above the lower cushion layer 30. The air-conducting cushion layer 32 is covered by a top layer 34 which is composed here of an open-pore, “reticulated” foam. In addition, lines for a seat heater (not shown) can be laid within a top layer 34. Together, the lower cushion layer 30, the air-conducting cushion layer 32 and the top layer 34 form a cushion layer arrangement 36 which is covered by a cushion cover 38, for example made of leather or a textile.

To ventilate the seat, an air inlet 40, with a plurality of air inlet passages 42, which are placed within the lower cushion layer 30 and through which the air-conducting cushion layer 32 is supplied with fresh air, is provided.

Air inlet openings 44 are recessed within the seat cushion support 28 at points of overlap with the air inlet passages 42 within the lower cushion layer 30. The air passing into the air-conducting cushion layer 32 via the air inlet passages 42 can flow out of the cushion layer via an air outlet 46 that includes a plurality of air outlet passages 48 placed within the top layer 34. In this case, the air outlet passages 48 open out at the air outlet openings 20 within the cushion cover 38.

The seat ventilation functions as follows:

Relatively cool and dry air flows out of the region below the seat cushion support 28 via the air inlet openings 44 and the air inlet passages 42 into the air-conducting cushion layer 32. The vehicle occupant's body moisture, which passes via the cushion cover 38 and the moisture-permeable, open-pore top layer 34 into the air-conducting cushion layer 32, is absorbed by the relatively dry and cold air. By this means, both the degree of moisture and the temperature in the region of the air-conducting cushion layer 32, which is arranged directly below the seat occupant, rise. The air, which is now heated and moist (and which endeavors to flow off upward on account of fundamental physical laws) passes in the direction of the air outlet 46, which is situated higher up, by means of the air outlet passages 48. The moist and relatively warm air then passes out of the seat cushion via the air outlet passages 48 and the air outlet openings 20 on the top surface 22 of the cushion and of the seat area 10, respectively.

In other words, in the case of the cushion according to the invention, use is made of the “chimney effect” in which relatively cold air (which experience has shown to predominate in a region in the vicinity of the vehicle floor in a passenger cell of a motor vehicle) is sucked up by warm and moist air. For its part, the latter has been heated in the region of the air-conducting cushion layer 32 by the body moisture from the seat occupant and endeavors to flow off in the direction of the air outlet 46 situated higher up. Even without fans, this arrangement results in circulation that is sufficient to reliably transport away body moisture generated by the seat occupant. If the cushion cover 38 is formed from leather, then the latter can be provided with perforations which facilitate the flow of body moisture into the top layer 34 and the air-conducting cushion layer 32. If, by contrast, the cushion cover 38 is formed from a textile, such a perforation is normally not necessary.

The above-described chimney effect is determined not only by the fact that the air outlet 46 lies upward of the air inlet 40, but also by the length over which the air flow has to flow through the air-conducting cushion layer 32, which must be relatively small. For this reason, the air outlet 46 is arranged in the direct vicinity of the body in such a manner that the air outlet openings 20 are normally not covered by the seat occupant. The air outlet openings 20 are therefore arranged, for example, in a front central region of the seat area 10—between the thighs and knees of the seat occupant—or in the corner region between the top surface 22 and the outer side 24 of the side cheek 12. This arrangement ensures that, although the air flow flows through the entire region of the air-conducting cushion layer 32 below the seat occupant, the air flow then exits relatively close to the seat occupant. In other words, in comparison to the prior art known to date, the period of residence of the air flow within the air-conducting cushion layer 32 is reduced or minimized. This results in a relatively strong air flow within the air-conducting cushion layer 32 and accordingly also in very good transportation away of the body moisture.

As can also be seen from FIG. 2, the air inlet passages 42 of the air inlet 40 are offset in relation to the air outlet passages 48 of the air outlet 46, so that air does not flow directly from the air inlet 40 to the air outlet 46.

As an alternative to the air outlet passages 48, the top layer 34 could be formed, at least in the region of the air outlet 40, from a highly air- or moisture-permeable material. In this case, the moist and warm air would then exit from the air-conducting cushion layer 32 not via the air outlet passages 48 but rather via a, for example, open-pore foam. If appropriate, the air outlet openings 20 can also be formed from a correspondingly large-meshed cushion cover 38 made from a textile. However, the flow of air through the air-conducting cushion layer 32 below the seat occupant should always be ensured. It is clear that, if appropriate, the lower cushion layer 30 can also be designed as an air-conducting cushion layer.

Finally, FIG. 3 illustrates a backrest cushion of a vehicle seat, which is designed substantially identically to the seat cushion. The present backrest cushion also comprises a seat area region 10 which is surrounded by side cheeks 12. A head restraint 50 can be seen on the top side of the backrest cushion.

Furthermore, a plurality of air outlet openings 20 of an air outlet 46, which openings correspond in their design to those of FIG. 2, is provided in the upper central region of the seat area 10. In a lower region of the seat area 10, the air inlet 40 (indicated by dashed lines in FIG. 3) which likewise comprises a plurality of air inlet openings 44 designed essentially in accordance with FIG. 2 can be seen on the rear side of the backrest cushion. The chimney effect, in which the relatively dry and cold fresh air flows in the region of the air inlet 40 into the air-conducting cushion layer 32, then absorbs body moisture over the course of its passage to the air outlet 46 and is correspondingly heated, and finally leaves the backrest cushion again via the air outlet openings 20, is therefore also ensured in the present exemplary embodiment. Furthermore, it is apparent that the air outlet openings 20 are arranged in a region above the shoulders of the seat occupant such that they are normally not covered by the seat occupant.

The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. 

1.-11. (canceled)
 12. A vehicle seat cushion having a layer arrangement that is covered by a cushion cover, said cushion comprising: an air-conducting cushion layer; at least one air inlet through which air can enter the air-conducting cushion layer; and at least one air outlet which is assigned at least one air outlet opening, through which the air can exit after flowing through the air-conducting cushion layer; wherein at least one air outlet opening is arranged within the cushion cover.
 13. The cushion as claimed in claim 12, wherein the at least one air outlet opening is arranged in a front central region of a seat area of a seat cushion.
 14. The cushion as claimed in claim 12, wherein the at least one air outlet opening is arranged in the region of a side cheek of the cushion.
 15. The cushion as claimed in claim 12, wherein the at least one air outlet opening is arranged in a corner region between a front top surface and a side of the cushion.
 16. The cushion as claimed in claim 12, wherein the at least one air outlet opening is arranged in an upper central region of a seat area of a backrest cushion.
 17. The cushion as claimed in claim 12, wherein the cushion cover has a plurality of perforation openings as air outlet openings.
 18. The cushion as claimed in claim 12, wherein a top layer is provided between the air-conducting cushion layer and the cushion cover, via which the air passes from the air-conducting cushion layer to the air outlet opening.
 19. The cushion as claimed in claim 18, wherein air outlet passages are provided within the top layer, via which the air passes from the air-conducting cushion layer to the air outlet opening.
 20. The cushion as claimed in claim 18, wherein the top layer between the air-conducting cushion layer and the air outlet opening is formed from a highly air-permeable material.
 21. The cushion as claimed in claim 12, wherein that the air inlet is arranged below the air outlet.
 22. The cushion as claimed in claim 12, wherein the air inlet is offset in relation to the air outlet.
 23. A vehicle seat cushion comprising: a plurality of layers disposed substantially parallel to a supporting surface of said seat cushion at least one of said layers being an air-conducting layer that is made of an air permeable material; at least one air inlet, through which air can enter said air-conducting inlet; at least one air outlet, through which air can exit said air-conducting layer; wherein, said at least one air outlet is positioned at a first end of said air-conducting layer; said at least one air inlet is positioned at a second end of said air-conducting layer, opposite said first end, such that air which enters said at least one air inlet must traverse substantially an entire length of said air-conducting layer in order to exit said at least one air outlet; said at least one air outlet is positioned higher in a vertical direction than said at least one air inlet. 